9-deoxy-9a-methylene isosteres of pgi.sub.2 and process for their preparation

Abstract From the Canadian patent

This invention relates to compounds having the following formula (I) wherein, R is chosen from the group a) a free or esterified carboxy group; b) -C(OR')3, where each R' group is independently C1-C6 alkyl or phenyl c) -CH2-R", where R" is hydroxy or C2-C7 alkoxy; d) where Ra and, are chosen independently from the group hydrogen C1-C6 alkyl, C1-C6, alkanoyl and phenyl; e -C?N; f) a radical; g) -CHO; h) a , radical where each X' is independently-O- or -S- and the R'a and R'b groups, whether the same or different, are C1-C6 alkyl or together form a straight or branched C2-C6 alkylene chain; D is chosen from the group: -CH2-, ?CH-OH (cis), (trans), -C?C-, ?C=O, -O-, -S-, an ?N-Rc where Rc …